Field of the Disclosure
The disclosure generally relates to an apparatus and method for a redundant valve system used to regulate bleed air from turbine engines. Specifically, the disclosure relates to a redundant valve system with two pressure regulating valves coupled and configured to reduce weight, reduce bulk, and increase reliability.
Related Art
Pressure regulating valves have applications in a wide variety of areas that use pressurized fluids to drive pneumatic systems. These systems typically require one or more pressure regulating valves controlled through electronic systems to permit operation remotely. One application for these pressure regulating valves are in aircraft systems that utilize a turbine engine.
Because these pressure regulating valves are used in critical functions of the aircraft, such as the de-icing of engine cowls, it is important to introduce redundant valves in the event one of the valves fails. It would be desirable to place two pressure regulating valves in series in order to provide a redundant valve system for de-icing of the engine cowls and the like. However, due to quick changes in pressure of the bleed air and the short distance between the valves in some prior art systems, the pressure gradient across the valves often fluctuates quickly. This rapid change in pressure may cause undesirable oscillation in operation of the valves and early failure of the valves. The industry solution to this problem has been to separate the valves using an extended duct of several feet in length (e.g., at least 4 feet in length). This increased distance between the valves allows the pressure gradient between the valves to be less susceptible to fluctuations in pressure. However, the introduction of an additional duct adds unnecessary weight, bulk, and parts in a pressure regulating system that needs to be compact and light weight.
Accordingly, there is a need for a redundant pressure regulating valve system that is resistant to oscillation of the valves while also being compact and light weight.